The hydraulics bleed down fairly quickly when the tractor is turned off. It works good otherwise when the engine is running. I think this started after I tried to lift something too heavy and lifted the front tires off the ground. Is it OK to keep using it like this or does it need a rebuild?GP

The reason why the hydraulics drop when a SA or Cub is shut off is because hydraulic fluid is leaking from or around the piston in the TC unit. The hydraulic fluid with leak into the head of the TC or past the O rings on the piston (two O rings in the wall of the piston shaft. Try replacing the head gasket first (no gasket sealer and use a torque wrench to torque down the head). Be sure to keep the insides of the TC nice and clean.

Very common issue, and as long as it is not leaking externally or leaking from the pump into the crankcase I wouldn't worry about it too much.

In addition to the sources Spaceghost mentioned, I think the leak could come from any of the o-rings inside the TC block. If I was going to take it off the tractor I would just go ahead replace all the o-rings and gaskets. CaseIH should have a kit for it--be sure to get the part # off the TC block because there were some changes to the TC during Super A production.

If you keep having to add oil to the TC unit, but no sign of an external leak, it is leaking past the seal in the pump and going into the engine crankcase. That is not the problem with the lift dropping though. The C oil is not a good engine lubricant, and that needs to be fixed and the engine oil changed. The seal for the pump is NOT included in the TC rebuild kit, and is also dependent on which pump you have. You can get the seal from Case/Ih, or take your old one to your local Carquest, NAPA, etc.